(gnus-article-prev-page): Rewrite to realize smooth scrolling under XEmacs.

(gnus-article-next-page):Ditto.

diff --git a/lisp/gnus-art.el b/lisp/gnus-art.el
index a4c6fb5..ee3b041 100644 (file)
--- a/lisp/gnus-art.el
+++ b/lisp/gnus-art.el
@@ -3701,48 +3701,53 @@ If given a numerical ARG, move forward ARG pages."
 If end of article, return non-nil.  Otherwise return nil.
 Argument LINES specifies lines to be scrolled up."
   (interactive "p")
-  (move-to-window-line -1)
-  (if (save-excursion
-       (end-of-line)
-       (and (pos-visible-in-window-p)  ;Not continuation line.
-            (eobp)))
-      ;; Nothing in this page.
-      (if (or (not gnus-page-broken)
-             (save-excursion
-               (save-restriction
-                 (widen) (forward-line 1) (eobp)))) ;Real end-of-buffer?
-         t                             ;Nothing more.
-       (gnus-narrow-to-page 1)         ;Go to next page.
-       nil)
-    ;; More in this page.
-    (let ((scroll-in-place nil))
-      (condition-case ()
-         (scroll-up lines)
-       (end-of-buffer
-        ;; Long lines may cause an end-of-buffer error.
-        (goto-char (point-max)))))
-    (move-to-window-line 0)
-    nil))
+  (let ((start (window-start))
+       end-of-buffer end-of-page)
+    (save-excursion
+      (move-to-window-line -1)
+      (if (<= (point) start)
+         (progn
+           (forward-line 2)
+           (setq start (point)))
+       (forward-line 1)
+       (setq start nil))
+      (unless (or (cond ((eq (1+ (buffer-size)) (point))
+                        (setq end-of-buffer t))
+                       ((eobp)
+                        (setq end-of-page t)))
+                 (not lines))
+       (move-to-window-line lines)
+       (unless (search-backward "\n\n" nil t)
+         (setq start (point)))))
+    (cond (end-of-buffer t)
+         (end-of-page
+          (gnus-narrow-to-page 1)
+          nil)
+         (t
+          (if start
+              (set-window-start (selected-window) start)
+            (scroll-up lines))
+          nil))))
 
 (defun gnus-article-prev-page (&optional lines)
   "Show previous page of current article.
 Argument LINES specifies lines to be scrolled down."
   (interactive "p")
-  (move-to-window-line 0)
-  (if (and gnus-page-broken
-          (bobp)
-          (not (save-restriction (widen) (bobp)))) ;Real beginning-of-buffer?
-      (progn
-       (gnus-narrow-to-page -1)        ;Go to previous page.
-       (goto-char (point-max))
-       (recenter -1))
-    (let ((scroll-in-place nil))
-      (prog1
-         (condition-case ()
-             (scroll-down lines)
-           (beginning-of-buffer
-            (goto-char (point-min))))
-       (move-to-window-line 0)))))
+  (let (beginning-of-buffer beginning-of-page)
+    (save-excursion
+      (move-to-window-line 0)
+      (cond ((eq 1 (point))
+            (setq beginning-of-buffer t))
+           ((bobp)
+            (setq beginning-of-page t))))
+    (cond (beginning-of-buffer)
+         (beginning-of-page
+          (gnus-narrow-to-page -1))
+         (t
+          (condition-case nil
+              (scroll-down lines)
+            (beginning-of-buffer
+             (goto-char (point-min))))))))
 
 (defun gnus-article-refer-article ()
   "Read article specified by message-id around point."